The Behaviour of Sulfonate Solutions in the Presence of Polyelectrolytes

The effects of polyelectrolytes such as silicates and phosphates on the dissolution/precipilation/redisolution of alkylbenzene sulfonate in multivalent cation aqueous solution have been studied. It turns out that the addition of polyelectrolytes causes an increase in the tolerance of sulfonate to multivalent ion and this effect depends upon the concentration and the chelation of polyelectrolytes. A thermodynamic model based on the solubility product of the precipitate and the theory of electric double layer is presented for the precipitation and redissolution of alkylbenzene sulfonate in aqueous solutions of multivalent cation. Reasonable agreement between theory and experiments for alkylbenzene sulfonate/calcium chloride systems is obtained with or without polyelcctrolytes.